Collection devices are a type of cap and container combination commonly used for receiving and storing biological samples for delivery to clinical laboratories, where the samples may be analyzed (e.g., to determine the existence or state of a particular condition or the presence of a particular infectious agent, such as a virus or bacterial microorganism, or to perform genotyping, such as for livestock traceability), banked, and/or archived. Since samples can contain pathogenic organisms, it is important to ensure that collection devices are constructed to be substantially leak-proof during transport from the site of collection to the site of analysis. It is also important that the device be substantially leak-proof in order to avoid contamination and maintain the integrity of the sample. This feature of collection devices is especially important when the clinical laboratory and the collection site are remote from one another, increasing the likelihood that the collection device will be inverted or severely jostled during transport and potentially subjected to substantial temperature and pressure fluctuations. Furthermore, it is important that the collection devices are convenient for use by non-technical individuals.
As is known, genotyping and disease detection can be done using biological samples collected from a subject to be tested. In order to perform genotyping and disease detection tests, people typically take venous blood, hair, or tissue samples, but these can be difficult to collect and process. One alternative is to collect biological samples that contain nucleic acids, which are easier to process than the above-mentioned samples and can also be used for genotyping and disease detection. Nucleic acid-containing biological samples include, for example, saliva, sputum, vaginal and nasal mucosal samples. In addition to being easier to process, the procedures for collecting nucleic acid-containing biological fluids tend to be less invasive than taking venous blood, hair, or tissue samples.
Typically collection of biological fluids (other than venous or arterial blood) are easier to collect and more readily accessible and the methods for collection of such biological fluids are less invasive for the donor and less expensive to perform. Highly trained professionals like physicians, phlebotomists and veterinarians are required for the collection of venous or arterial blood and some tissues. An untrained person in an unsupervised setting (e.g., a home, a farm) can collect most biological fluids.
Other biological samples that are routinely collected and stored include, but are not limited to, swabs of potentially contaminated (e.g., by biological agents, radioactive isotopes, etc.) surfaces, biological tissue, such as epithelial cells, tissue plugs or slices (e.g., from carcasses) or geological samples.
One standard method of collecting biological samples involves employing a sample collection device, such as a swab, brush or knife, to the biological sample to be collected and then placing the sample collection device in a stoppered tube. Optionally, the tube may be prefilled with a preserving solution and/or transport medium. The tube is then sent to a laboratory where the nucleic acid contained in the sample can be tested.
This method of collecting the biological samples can however result in the contamination of the sample. Either the stopper needs to be removed prior to applying the sample collection device to the biological fluid, thus increasing the risk of undesirable material entering the tube or coming into contact with the stopper while the sample is gathered, or the sample collection device with the gathered sample needs to be set down while the stopper is removed from the tube, thus increasing the risk of direct contamination of the sample on the swab. To minimize these problems, typically, a second pair of hands and/or a rack/sterile container/bag must be provided, which makes the collection process more complicated and time consuming.
Another source of contamination and cross-contamination is the user's handling of the sample collection device. The user must grip the handle of the swab or other collection device to collect the sample from the source. Even with gloved hands there is significant risk of introducing contaminants to the tube, since the entire swab/collection device is deposited in the tube.
Concerns relating to sample cross-contamination are also inherent to the use of a stopper. Such concerns are especially acute when the sample being collected is to be used in molecular diagnostic techniques employing hybridization and/or amplification of nucleic acids, such as, but not limited to, polymerase chain reaction (PCR), branched chain DNA (bDNA) assays, transcription-mediated amplification (TMA), and reverse transcriptase polymerase chain reaction (RT-PCR). Since amplification is intended to enhance assay sensitivity by increasing the quantity of targeted nucleic acid sequences present in a specimen, transferring even a minute amount of specimen from one container, or target nucleic acid from a positive control sample, to another container can cause confounding or inaccurate results. Similarly, hybridization-based assays may be affected by cross-contamination of samples.
When removing the stopper from the tube or sample collection container, it is possible that some of the preserving solution and/or transport medium could spill due to the pulling motion necessary to remove the stopper. Similarly, after sample collection, if any sample is on the stopper it can spray or spill as the stopper is removed. This is even more likely when the sample collection has to be done by people who are not familiar with such apparatuses, such as a farmer who needs to collect biological samples from his animals for testing or genotyping (e.g., for traceability and parentage).
Additionally, the stopper could leak or become dislodged during transportation from the place where the sample was collected to the laboratory. This problem is made more obvious when the user is an untrained or non-technical person.
Furthermore, it can be difficult to determine if the stopper has been sufficiently pushed into the opening of the container to provide a proper seal.
Additionally, stoppers are often made of rubber, or a similar material, that includes components that can contaminate the biological sample. This can be particularly problematic when the sample is to be used in nucleic acid analysis since components of rubber that can leach into the sample are known to inhibit or interfere with nucleic acid amplification.
Finally, since the sample collection device is essentially loose inside the container once the sample has been collected, automated retrieval of the sample collection device for sample processing is difficult. Therefore, this step is usually performed manually, which can introduce both contamination and cross-contamination of samples.
Therefore, there is a need for an apparatus and method of collecting a sample that reduces the likelihood of contamination of the sample and of leaking or spilling of the preserving solution and/or transport medium prior to and following deposit of the sample.
Furthermore, obtaining samples of animal or human biological sample under farm and/or field conditions is particularly challenging due to the unpredictable behaviour of animals and/or the unsanitary or extreme nature of the farm or field conditions themselves.
Therefore, there is also a need for an apparatus and method for quickly and safely collecting biological samples.